Maybe prematurely I decided to release DiagROM 1.3

Sadly “I lost track” what is changed from 1.2.1 but in short some bugfixes, new memorycheck routine and it now handles Addresserror issues.

Please look at the history for all changes.

Decided to have 1.3 out now so I can get cracking on DiagROM V2.0 for real!